688401 has 24 divisors (see below), whose sum is σ = 1164800. Its totient is φ = 391608.

The previous prime is 688397. The next prime is 688403. The reversal of 688401 is 104886.

It is not a de Polignac number, because 688401 - 2² = 688397 is a prime.

It is a nialpdrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688403) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2976 + ... + 3198.

2⁶⁸⁸⁴⁰¹ is an apocalyptic number.

It is an amenable number.

688401 is a deficient number, since it is larger than the sum of its proper divisors (476399).

688401 is a wasteful number, since it uses less digits than its factorization.

688401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 233 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 688401 is about 829.6993431358. The cubic root of 688401 is about 88.2972472354.

It can be divided in two parts, 688 and 401, that added together give a square (1089 = 33²).

The spelling of 688401 in words is "six hundred eighty-eight thousand, four hundred one".